The setup instructions say that you should be able to just drop jstl.jar and standard.jar into your web app's lib directory and go. But neither of these jars contain the org.saxpath package that is used by a number of the XML tag implementations. All supporting classes for the JSTL implementation should be included in standard.jar.
Including other packages in a distribution's single JAR is not standard, modern practice, and it is not required by the current instructions: To use this distribution with your own web applications, simply copy the JAR files in the 'lib' directory to your application's WEB-INF/lib directory. If you know of other instructions that disagree with this and haven't been updated, please let us know; the information would be appreciated. But the current organization of classes is intentional and shouldn't be inconvenient.
OK, consider this bug a request to fix the documentation. Here's the offending snippet: "To use the Standard 1.0 taglib, include the 'jstl.jar' and 'standard.jar' files in your application's WEB-INF/lib directory." http://jakarta.apache.org/taglibs/doc/standard-doc/GettingStarted.html
Thanks - all fixed now. Changes should show up on the site tomorrow.